UKRoman

Definitely radial. I’ve actually done some more digging around and there are a few threads on CN about ‘butterfly stars’ on the FSQ-85. There seems to be two competing theories. Firstly that this an artefact caused by the Petzval design. The second one is that it’s caused by severe vignetting. On the first theory I’m not so sure as I’ve not seen any images taken with an FSQ-106 that have this issue. But then again the image circle of the 106 is so large that maybe it’s not picked up by the vast majority of cameras as they only capture images from the centre of the field. On the second theory, this seems plausible as I’ve seen references to exactly the same effect with a Rokinon 135mm lens with a heavy vignette. That said, I’m starting to think it might be a combination of design exacerbated by vignette, which is itself caused by the field flattener. Either way I’m not sure there’s a way round it with my imaging train setup apart from good post processing. Happy to hear other opinions and suggestions though👍 Thanks

Agreed, and yes everything is tightened down in the imaging train.

Hi All, Although I bought my first serious telescope for visual observing back in 1992, I'm still relatively new to Astrophotography. In the last 12 months I've played with a few small refractors to get the hang of things, including a WO ZS73 and a Redcat 51. I've used both of these with a modified Canon 800D and more recently a ZWO ASI2600MC Pro. Having found my feet somewhat in this fascinating branch of Astro I decided to take the plunge a buy a Takahashi FSQ-85EDX, a dream scope. First light was only brief break in the clouds, giving me an hour on the Horsehead nebula. However after a quick process in Astropixel Processor I managed to draw out a reasonable image for my first attempt with this gear (new ASIAIR pro and EAF too). I'm not totally unhappy with it, but have been surprised to see some strange artefacts to the stars around the outer third of the image (particularly noticeable on the bright star at the bottom left). At first I thought I'd done something wrong with the processing, but after reading a number of posts on the forums it seems that 'butterfly' stars are the result of vignetting. So I stretched one of my Flats and sure enough there appears to be significant vignetting. To be honest I've not seen vignetting this severe before on either of my other small refractors. The imaging train for the attached image was FSQ-85EDX > 1.01 Flattener > M54 to M42 Adapter > M42 Spacers > ZWO Filter draw with Optilong LPro filter > ASI2600MC Pro. Although I haven't tried to image with my Canon 800D (also APSC) on the Tak, I have checked the vignetting with this camera and it appears to be around the same level, so I'm guessing I'd see the same artefacts around bright stars. I’ve also swapped the M42 adapters for M48 into the filter draw with the 2600MC Pro but the vignette looks unchanged. Just wondering, does anyone else with an FSQ-85 see this kind of butterfly stars artefact with an APSC camera? If so, can it be prevented or maybe processed out in Post? Thanks

I’ve had one if these mounts for a few weeks now. The portability is excellent. I got one because I was fed up of carrying my heavy AZ-EQ6 Pro up and down stairs. This is so light that I move it around pretty much completely assembled. On that front I’m completely happy. Guiding is interesting though. I don’t seemed to have cracked that yet. The best figures I’ve had via my ASIAIR Pro are around 1.5” and it can vary up and down quite considerably. That said, it doesn’t seem to affect my images, which is what counts at the end of the day. I intend to try the mount with my laptop and PHD2 to see if I get better figures, just in case it’s the ASIAIR that’s simply reporting it differently. I’m using the mount on an Artcise AS90C tripod, which provides a solid base when used in conjunction with an 85mm refractor. All-in-all the RST-135 is doing what I wanted it for and so far I haven’t gone back to my AZ-EQ6. So I’m pretty happy with it.

Yeah I’m guessing the Christmas holidays might slow down any response. I emailed Andy from Astronomiser, who got back to me quickly. Unfortunately he said that he doesn’t convert mirrorless cameras yet, only DSLRs. I did have a Canon 800D camera modified by Baader in Germany earlier in the year. They did a fantastic job. But they’ve removed the UK from their website as a country that they provide direct services too, presumably because of Brexit. In any case they only modify APSC cameras. The other company I’ve spotted is JTW Astronomy in Holland. I’ve not approached them yet as they seem to get mixed reviews in terms of the amount of time they take to do the work. Though most people seem happy with the work they eventually do. I’ll leave it a week or two to see if Juan replies to my enquiry. Thanks for your suggestions.

Apologies for the delay in replying. I did try emailing Juan but haven’t had any response.

I actually use your option B for my AZ-GTi and it works fine. The TalentCell lasts all night driving the mount without running out of juice. I went through several power solutions before I settled on this one and I haven’t had any issues so far. One of the big advantages is that it doesn’t shut down automatically due to the low current draw of the AZ-GTi, which my Celestron Powertank Lithium Pro does after just a few minutes.

Hi All, Would anyone know where I could get a Canon EOS R modified? I’m looking to get it modified for additional Ha sensitivity but with the option for daytime photography using a custom white balance or OWB clip-in filter? Thanks

Nice one, thanks. That’s a great looking rig. I’ve got mine mounted on an RST-135 at the moment; trying for a portable set up as I’m looking to travel for dark skies. Can’t wait to get it all up and running 👍

Thanks for the tip, that’s a nice looking product👍 I’ve heard that some folks have tilt issues, so I’ll investigate this item when I’ve had a chance to do some imaging to see how the stock CAA is performing. Are you connecting a dedicated Astro-camera rather than a DSLR? If so which adatpters are you using?

Hi All, I've just picked up a Takahashi FSQ-85EDX; dream scope 🙂. I'm now trying to figure out how to attach my ZWO ASI2600MC Pro to it. I can see from the Takahashi system chart that I think I'll need the Aux ring (TKA23250) and the CA-35 (TKA23201). But then there's also a reference to a Wide T-mount adapter as the final connection to a CCD camera. When I look up Wide T-mount adapters they seem to be aimed at DSLR cameras rather than my OSC camera. Does anyone have any idea which adapter to use for this final connection to the 2600MC Pro? Thanks

Interesting. My gotos are pretty much bang on. Could it be a backlash issue maybe? I have noticed that the RA axis seems to be slightly spring loaded so that when the RA clutch is tight the backlash is minimised by spring loading towards the west.

Yeah, from what I’ve read it’s seems to be more apparent with certain types and makes of imaging train components. I’ve no idea if the Canon R would exhibit the same issues after an Astro-mod.

Hi All, Just considering camera options for my mobile astrophotography rig. I’ve decided on a full frame DSLR to provide a self powered alternative to a dedicated Astro-camera. I’ve been looking at the Canon RA but it seems quite pricey for what it is, as well as the reported issue with strange halos around bright stars. But the Canon R or even RP seem to be much more sensibly priced for the features they offer. The question is would an Astro modified R or RP offer a cheaper yet viable alternative to the RA. Thoughts welcome. Cheers

Nice one, thanks for your help. I'll give it a go next clear night 👍

Hi, Apologies, I’ve only just seen your post. That’s a good tip, many thanks. I’ll give it a go 👍 Have you tried dithering without the Dec guiding activated?

Yeah I can see that now. I realised it was flipped when I had it set up next to my AZ-EQ6, and I confirmed it when I set up the Star Adventurer mount. I thought it was odd. But clearly my misunderstanding. Definitely a fantastic upgrade whichever way round the scale is flipped. 👍

I have several mounts and scopes, but for visual use my Skywatcher EVO Star 80ED sat on the AZ-GTi is without doubt the one that gets the most use. It’s so easy to set up and can be up and running in minutes. I have recently tried it in EQ mode using a Redcat and the ASIAIR Pro, but that wasn’t particularly successful. I struggled to get it polar aligned and even when I did the guiding was terrible. That said the recent firmware update to the ASIAIR has apparently introduced a few guiding issues in certain circumstances, so I’ll have another go when they’re sorted. But for visual use with a small refractor in AZ mode, I love it.

Ah, my bad. I’ve just switched out the Redcat on the AZ-GTi for a DSLR on the Star Adventurer mount head. Using this configuration the WO wedge is in the opposite orientation, so the latitude scale is the right way round. That’s what I love about this hobby, you learn something ew every day 😃

Hi All, I currently have a Skywatcher AZ-EQ6 GT which I really like. It’s a great mount and mine tracks beautifully well, however I find the weight is excessive. So I’m looking at lighter and more portable, but equally capable alternatives. This has led me to consider the iOptron CEM40. It looks like it fits my requirements perfectly. The only thing that concerns me is that the tripod/mount setup and then adjustment during polar alignment looks to involve an Allen key and small bolts and washers to lock things down. This sounds like a recipe for disaster in the dark. Before I make a decision on whether or not to pull the trigger on the CEM40, I was wondering if anyone with experience of setting up this mount finds it to be an issue? Does using an Allen key to tighten down the adjustment screws affect the polar alignment? Or do the benefits of the mount out-way the disadvantages? Thanks in advance.

Yeah, good call. I guess that's about right. It seems a bit of an odd way of representing it though. My AZ-EQ6 shows around 52 degrees, which you just dial straight in. Although I've only just noticed the scale markings on that count the opposite way round, so I think you're right. I wonder why William Optics have done it like this. In any case it makes no practical difference, it's a wonderfully engineered wedge 🙂

I've been using a waterproof kettlebell barbecue cover from Amazon. £13. It seems to do the job so far. In fact I can see one almost identical in the background of the photo above. 🙂

Hi All, Not that it matters in anything other than a cosmetic sense, but has anyone else with a William Optics Wedge noticed that the latitude scale might not represent actual latitude in degrees? I'm at 53 degrees North and the scale reads 36 when I'm polar aligned. Or am I missing something obvious? Cheers

Agreed, the light pollution is a real issue. I’m in a 7, but fortunately only a stones throw from the countryside, which really helps. It’s actually one of the reasons my C925 has remained largely unused, as I found that a small refractor is much easier to transport to darker skies.

Great tip, thanks Mark. Tbh I hadn’t noticed those until you mentioned it. I’ll get the gorilla glue out later 😃👍 So much has changed in Astronomy since I last dipped my toes in. I’m really enjoying it again thanks to all the gadgets that help make observing and image capture a pleasure. Though I have to say they bring their own challenges. The biggest disappointment for me is that I hadn’t really noticed how rare clear skies are in the UK until I sat there with my shiny new gear waiting for a clear night. On average it seems to be around once a month that I can actually get out. I’m consoling myself with the thought that the anticipation is half the fun 😊👍